While fooling around in Minecraft spawning monsters, I created an iron golem. The iron golem killed all the monsters on land, but afterwards it went to the edge of a pool several monsters were in and just stared at them.

What I expected to happen was that considering iron golems don't actually get hurt in water (compared to lava), the iron golem would go in the water and get rid of the zombies.

What actually happened was that the iron golems just stared at the zombies at the edge, as if it was afraid of getting wet.

Steps to reproduce:
1. Create a pool of water (or find a natural lake nearby).
2. Spawn a bunch of zombies, skeletons or other hostile mobs in the pool.
3. On land, build an iron golem. You should find that the iron golem walks to the edge of the pool, and just glares at the nearest hostile mob.